I wonder if that is the same roller bearing MB uses in the vacuum pump? If it is, I wonder if any of them had the plastic race that disintegrates over time. I'm thinking about the vacuum pump failure threads elsewhere on the forum where the bearing comes apart.

So lets say they did use the same plastic race.... Is there enough clearance for the ball bearing to get out of the pump and get into the engine?

(Also, that non-return valve looks to be the same one used in the vacuum pump.)

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1984 300D 398K-daily driver
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